The value of stress under air pressure test shall not exceed 80% of the yieldpoint of the material in test temperature;
气体压力试验时的应力值，不得超过试验温度下材料屈服点的80%。
2
The value of stress under hydraulic pressure test shall not exceed 90% of the yieldpoint of the material in test temperature;
液体压力试验时的应力值，不得超过试验温度下材料屈服点的90%；
3
In order to prevent the yield-point elongation occurring the manganese equivalence in alloy must exceeds 1.61%, and the threshold value of Martensite volume fraction is 7%.